| 摘要 |
PROBLEM TO BE SOLVED: To provide a press working oil for a galvanized steel plate excellent in stamping workability, rust-prevention, and degreasing character. SOLUTION: This oil comprises 30-90 pts.wt. base oil, 1-20 pts.wt. rust- preventive additive of an alkyl sulfonate, a carboxylic acid or its salt, 1-20 pts.wt. lubricant additive of a trialkyltrithiophosphate, 1-20 pts.wt. inactive S type extreme pressure additive of a fatty acid ester contg. 5-15% S, a fat with bonded S, or a compd. in which an olefin is bonded to a fat, 1-10 pts.wt. oiliness agent (1) of a partial ester of a polyhydric alcohol, and 5-30 pts.wt. oiliness agent (2) of a full ester of a polyhydric alcohol, and the ratio of the trialkyltrithiophosphate to the inactive S type extreme pressure additive is 1:15-2:1, its active S is not more than 0.5%, the ratio of the partial ester compd. to the full ester compd. is 1:10-10:1, its saponification value is not higher than 130 mgKOH/g, and its kinematic viscosity at 40 deg.C is 2-30 mm2/s. |
